There has been a significant decline in the use of metal-on-metal (MoM) bearings due to concerns regarding adverse reaction to metal debris (ARMD). The Medicines and Healthcare products Regulatory Agency (MHRA) recommends annual follow-up for life with blood Cobalt (Co) and Chromium (Cr) ion level measurement in all MoM THRs with femoral head size greater than or equal to 36mm. We present the serial ten year serum Co and Cr levels in a cohort of large head MoM THRs and analyse the utility of measuring serum ions levels annually. All patients who underwent unilateral large head MoM THR between January 2004 and December 2006 were included in this prospective study. Annual serum Co and Cr measurements were measured. Clinical case notes and radiographs were reviewed for failure, revision surgery and the occurrence of ARMD. Mann Whitney test was used to analyse changes in serum Co and Cr levels. Receiver Operating Characteristic (ROC) curve was plotted based on their sensitivity and specificity to detect ARMD. 256 patients were included. There was a significant increase in serum ion values in the first two years. After 7 years, there was no significant change in Co values(p=0.78) and there was a decline in Cr value after 9 years(p<0.001). With 7 µg/l as the cut-off value, the sensitivity and specificity of Co was 82.1% and 65.5% and of Cr was 53.5% and 91.3%. Annual follow-up of patients with MoM THR based on the MHRA guideline to obtain serum metal ion levels can cost about £9 million/year. Our study noted poor discriminatory ability for both Co and Cr values in the ROC curve. There is poor correlation between serum metal ion levels and the occurrence of ARMD on MARS MRI. Based on our results we find limited utility in doing ion levels after 7 years in asymptomatic patients.
High failure rates have been associated with large diameter metal-on-metal total hip replacements (MoM THR). However there is limited literature describing the outcomes following the revision of MoM THR for adverse local tissue reaction (ALTR). A total of 98 large diameter MoM THRs underwent revision for ALTR at our institution. The data was obtained from the clinical records and included the demographics, intra-operative findings of ALTR and post-operative complications. Any subsequent procedures and re-revision for any reason was analysed in detail. The clinical outcome was measured using functional outcome scores using the Oxford hip score (OHS), Western Ontario and McMaster Universities osteo-arthritis index (WOMAC) score and Short Form (SF12). The mean age of the patients at the time of revision was 58.2 yrs. At a mean follow-up of 3.9 years (1.0 to 8.6) from revision for ALTR, there were 15 hips (15.3 %) with post-operative complications and 8 hips (8 %) requiring re-revision. The Kaplan–Meier five-year survival rate for ALTR revision was 91 % (95% confidence interval 78.9 to 98.0). There were no statistically significant predictors of re-revision. The rate of postoperative dislocation following revision was 9.2% (9 hips). The post-operative functional outcome depends on the intra-operative findings of tissue destruction secondary to ALTR. The short term results following revision of large diameter MoM THR for ALTR are comparable with other reports in the literature. The use of constrained liners reduces the incidence of post-operative dislocation. There is an increased risk of postoperative instability following revision THR for ALTR. Early identification and intervention seems to be the logical approach in the management of patients with ALTR.
Cartilage lesions in chronic lateral ligament deficiency are common with the incidence rates mentioned in the previous literature up to 30%. However, other intra-articular pathologies in the unstable ankle have received little attention. Anterolateral impingement associated with synovitis and scarring is a less recognised feature in the treatment of chronic instability. The aim of our study was to ascertain the incidence of chondral and anterolateral impingement lesions in the symptomatic lateral ligament complex deficiency. We performed a retrospective study of all consecutive patients who underwent modified Brostrom repair for symptomatic recurrent instability of the ankle. All patients underwent a MRI scan prior to surgery. Arthroscopy was performed in all the patients before lateral ligament reconstruction. Seventy seven patients with 78 ankles were included in the study. Patients who had previous ankle surgery or inflammatory arthropathy were excluded. Data was obtained from clinical and radiological records. Arthroscopic findings were recorded in detail during the surgery.Background
Methods
Cartilage lesions in chronic lateral ligament deficiency are common with the incidence rates mentioned in the previous literature up to 30%. However, other intra-articular pathologies in the unstable ankle have received little attention. Anterolateral impingement associated with synovitis and scarring is a less recognised feature in the treatment of chronic instability. The aim of our study was to ascertain the incidence of chondral and anterolateral impingement lesions in the symptomatic lateral ligament complex deficiency. We performed a retrospective study of all consecutive patients who underwent modified Brostrom repair for symptomatic recurrent instability of the ankle. All patients underwent a MRI scan prior to surgery. Arthroscopy was performed in all the patients before lateral ligament reconstruction. Seventy seven patients with 78 ankles were included in the study. Patients who had previous ankle surgery or inflammatory arthropathy were excluded. Data was obtained from clinical and radiological records. Arthroscopic findings were recorded in detail during the surgery.Background
Methods
A significant proportion of children with cerebral palsy (CP) are malnourished. This is particularly the case for trace elements, vitamins and minerals. Children with CP undergoing major orthopaedic procedures lose blood intra operatively leading to post operative anaemia. The aim of our study was to estimate the prevalence of low levels of serum ferritin in children with CP awaiting major orthopaedic surgical intervention. The ferritin levels and haemoglobin (Hb) were estimated pre-operatively in 35 children with CP (CP group) undergoing major orthopaedic surgery (Hip reconstruction or Single event multi-level surgery). During the same period, we randomly identified 1000 children (Control group) who underwent Ferritin estimation as part of routine investigations. A significant proportion of children in the study group had low levels of serum ferritin in spite of having normal haemoglobin. It is well-recognised that commencement of iron either orally or intravenously in the post-operative period does not accelerate recovery from anaemia secondary to blood loss. It is important to note that many patients who have normal Hb levels preoperatively are iron deficient. Hb estimation alone is inadequate in this group. We therefore conclude that children with cerebral palsy undergoing major orthopaedic surgery must have their ferritin levels estimated and optimised well in advance of their surgery.
The principles of revision total knee replacement are to understand the cause of failure, adequate surgical exposure, achieving appropriate soft tissue balance, restoration of limb and joint line alignment, correct implant alignment, and a good range of motion. It is a technically and economically demanding procedure and its successful performance requires thorough preoperative planning, adherence to the principles, availability of diverse implant options and adequate bone graft. We prospectively assessed the survivorship of Co-ordinate Ultra prosthesis (DePuy, Warsaw, Ind) used for revision knee arthroplasty. Forty-nine patients had 53 revision knee replacements performed by the senior author between April 1999 and September 2001. Seven patients (7 knees) had died. At a mean follow-up of 6 years (range: 5–7 years), 46 knees in 42 patients were available for review. None were lost to follow-up. There were 31 women and 11 men, with a mean age of 74.2 years. The reason for revision was instability in 39 knees, infection in 3 knees, pain in 2 knees and stiffness in 2 knees. Significant improvement was noted in the SF-12 PCS and WOMAC pain and stiffness scores at the latest follow-up. None of these patients required re-revision. None of the knees showed evidence of progressive loosening. Radio-opaque lines were found around the stems and were present in immediate post-operative radiographs; this did not indicate loosening or infection on further follow-up. Cumulative survival analysis (Kaplan-Meier method) was 100% at 7 years. Clinical and radiological outcome analysis has revealed that the Co-ordinate Ultra revision knee system continues to function satisfactorily at a mean follow-up of 6 years.
Percutaneous fixation is a well recognised technique in the treatment of three-part and four-part fractures of the proximal humerus. Minimal fixation of these fractures do show good functional outcome and may further reduce the incidence of avascular complications. We report a preliminary series of 11 patients who underwent percutaneous minimal fixation of such complex humeral fractures using a new technique. 11 consecutive patients (7 with three-part fractures and 4 with four-part fractures) treated by percutaneous limited fixation in our Hospital were involved in this retrospective study. There were 7 fractures with valgus displacement. Percutaneous technique was employed using small incisions and the fracture was reduced under image guidance. The three-part and the four-part fractures were essentially converted into two part fractures, i.e. only the greater and the lesser tuberosities were re-attached to head with AO cancellous screws after realignment of the fragments. The shaft of the humerus was not fixed to the head in any of the cases. All of these cases had a minimum follow-up of at least 6 months. The results were evaluated using the Constant -Murley Shoulder score. 1 out of 11 cases had to be converted to hemi-arthroplasty due to secondary redisplacement of the fracture. The remaining 10 cases showed good bony union although the greater tuberosity in 2 cases showed a residual superior displacement of 3mm and a residual valgus displacement in 2 out of 7 cases. There were no complications of avascular necrosis in any of the cases. Clinically, compared to the uninjured side the average constant score was 93.7% (range- 68.7% – 100%). 7 patients were very satisfied and 4 were satisfied with the operation. Percutaneous minimal fixation achieves good to very good functional outcome comparable to the conventional methods and theoretically reduces the incidence of infection, avascular necrosis and neurological complications.